The diesel pump nozzle is bigger than most petrol filler necks on the car, so it doesn't really fit. That makes it far less common to put the wrong fuel in a petrol car than putting petrol in a diesel car.

Plus, it's not as bad for a petrol engine to have diesel in it so there's usually not as much damage.

 

Here's what happens when you put diesel in a petrol car:

• Petrol ignites by a spark from the spark plugs.

• Diesel in a petrol engine clogs up the spark plugs and the fuel system.

• Engine misfires

• Unusual amount of smoke emitting from your exhaust

• Engine cuts out

• That means the car simply won’t start.

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It's a real pain. But it's not as bad as the damage that petrol can cause to a diesel engine. Your petrol engine shouldn't have any permanent damage once the fuel's drained out.